present tense同future tense的矛盾

I have a meeting next Friday morning. (會議早安排, 是schedule上)
I will take my driving courses next month. (現在暫時打算,可能下月因事會變)

THE FUTURE

(1) will/won’t + verb (最常用)
(2) present simple
(3) be + going to + verb
(4) present continuous
(5) be + about to + verb
(6) Other forms, Future continuous etc

只談論三種.

English does not have a future tense, but use a variety of verb forms to talk about the future. The choice often depends on whether we are making a prediction, expressing an intention or talking about an arrangement.

(1) will/won’t + verb
We use will, won’t (future simple) to talk about predictions which are based on guesswork or judgment.
I think interest rate will rise in Hong Kong next month.
She will like your gift, I’m sure.

We often use the same form to talk about a decision made at time of decision.
You look tired. I will cook the dinner tonight.
I will come with you at the weekend, whatever my parents say!

(2) present simple
We can use the present simple for future certainties like timetables, schedules or in the calendar. It is impersonal and more formal.
The tour departs on August 10th for a week.
Next Monday is a public holiday. (It is a fact)
The bus to the airport leaves in 20 minutes. (if scheduled)

I guess the bus to the airport will probably leave in 20 minutes. (我猜測)
The old man will turn 90 next Monday. (用 will,下星期一前,什麼意外事件可會發生)

There are some that-clauses and wh-clauses which have a present simple verb for the future.
I hope that you have a pleasant trip.
Don’t get lost, whatever you do.

(3) am/is/are going to + verb
We also use this form to make a prediction ( with evidence to justify the prediction) or for intentions (for actions that have already been decided on)
Look at those black clouds. It is going to rain. (prediction)
Cindy is going to study medicine at H.K.U. next year. (intention)

不如先解釋兩者之分吧。
present tense ，我們用於習慣，同時亦可用於與日曆﹑時間表有關的時候。
E.g. The park closes at nine o'clock in the summer.
這句是己有計劃好的，也就是與日曆﹑時間表有關。

而future tense 則是有一件事發生在未來的。
E.g. I will have a barbecue on Saturday.
這句是發生於未來。

兩者仿似一樣，都是發生於未來，但用future tense 的事件可發生變故，也就是說，這不一定會發生。

我用中文的方法重新解釋一次吧。
E.g. 我和朋友在星期日去唱K。 -------->這計劃好
我那天突然有事不能去。 --------------->雖然計劃好，但中途有變故。不能完全肯定那天一定會去，此刻，我們便會用future tense。

而present tense 則能完全肯定計劃會如常進行。因此，用present tense 比future tense 更加能肯定plan 好的進行。

應該就是這樣，若有不明，可以send e-mail 給我，我再好好解釋。

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http://www.comingzoo.com
http://www.pf23.com

我自己都去開, 希望可以幫到你~ ^T^
比我20分!